U.S. patent number 7,780,625 [Application Number 11/345,617] was granted by the patent office on 2010-08-24 for instrument for implanting sensors and solid materials in a subcutaneous location and method thereof.
Invention is credited to Gust H. Bardy.
United States Patent |
7,780,625 |
Bardy |
August 24, 2010 |
Instrument for implanting sensors and solid materials in a
subcutaneous location and method thereof
Abstract
An implantation instrument for implanting a substantially solid
material, including solid medication or drugs, in a subcutaneous
location and method are described. An incising shaft includes a
beveled tip with a cutting edge along a distal end. A syringe body
is affixed to a proximal end of the incising shaft. The syringe
body and the incising shaft each define a substantially
non-circular hollow bore extending continuously along a shared
longitudinal axis. The incising shaft bore does not exceed the
syringe body bore in girth. Both the incising shaft bore and the
syringe body bore are sized to receive the solid material. A
plunger is conformably shaped to the syringe body bore and has an
end piece facilitating deployment of the plunger assembly. The
plunger slidably fits within the syringe body bore and advances the
solid material through the syringe body bore and the incising shaft
bore into the subcutaneous location.
Inventors: |
Bardy; Gust H. (Seattle,
WA) |
Family
ID: |
24585873 |
Appl.
No.: |
11/345,617 |
Filed: |
February 1, 2006 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20060253065 A1 |
Nov 9, 2006 |
|
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
11025770 |
Dec 20, 2004 |
|
|
|
|
10222719 |
Aug 15, 2002 |
|
|
|
|
09644666 |
Aug 20, 2002 |
6436068 |
|
|
|
Current U.S.
Class: |
604/57; 604/60;
604/59 |
Current CPC
Class: |
A61M
37/0069 (20130101); A61B 2560/063 (20130101) |
Current International
Class: |
A61M
31/00 (20060101) |
Field of
Search: |
;604/57-64 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
PCT/US99/08353 |
|
Oct 1999 |
|
WO |
|
PCT/GB99/02389 |
|
Feb 2000 |
|
WO |
|
PCT/GB99/02393 |
|
Feb 2000 |
|
WO |
|
Primary Examiner: Lucchesi; Nicholas D
Assistant Examiner: Price; Nathan R
Attorney, Agent or Firm: Inouye; Patrick J. S.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This patent application is a continuation of U.S. patent
application Ser. No. 11/025,770, filed Dec. 20, 2004, abandoned,
which is a continuation of U.S. patent application Ser. No.
10/222,719, filed Aug. 15, 2002, abandoned; which is a continuation
of U.S. patent application Ser. No. 09/644,666, filed Aug. 24,
2000, no U.S. Pat. No. 6,436,068, issued Aug. 20, 2002, the
priority dates of which are claimed and the disclosures of which
are incorporated by reference.
Claims
What is claimed is:
1. A subcutaneous implantation instrument, comprising: a syringe
body comprising a non-cylindrical shaft that axially defines a
non-circular bore continuously throughout the length of the shaft,
wherein the bore comprises a cross section of at least five
millimeters in at least one orientation; a non-cylindrical incising
shaft comprising: an incising shaft body that axially defines a
non-circular bore sized to match the bore of the syringe body: a
beveled cutting blade comprising a beveled surface on a distal face
of the incising shaft body and a straight and sharpened cutting
edge cutting edge with rounded ends on each side of the cutting
edge that curve inwardly, wherein the cutting edge is defined only
along a bottom distal edge of the beveled tip; and an attachment
surface formed on a proximal end of the incising shaft body,
wherein the incising shaft is fixedly attached to a distal end of
the syringe body at the attachment surface; and a delivery
mechanism comprising a plunger longitudinally formed to slidably
fit within the bores of the syringe body and the incising
shaft.
2. A subcutaneous implantation instrument in accordance with claim
1, wherein the incising shaft is formed into a curve arced towards
the delivery mechanism.
3. A method for constructing a subcutaneous implantation
instrument, comprising: constructing a syringe body comprising a
non-cylindrical shaft that axially defines a non-circular bore
continuously throughout the length of the shaft, wherein the bore
comprises a cross section of at least five millimeters in at least
one orientation; constructing a non-cylindrical incising shaft
comprising: forming an incising shaft body that axially defines a
non-circular bore sized to match the bore of the syringe body;
creating a beveled cutting blade comprising a beveled surface on a
distal face of the incising shaft body and a straight and sharpened
cutting edge with rounded ends on each side of the cutting edge
that curve inwardly, wherein the cutting edge is defined only along
a bottom distal edge of the beveled tip; and forming an attachment
surface formed on a proximal end of the incising shaft body,
wherein the incising shaft is fixedly attached to a distal end of
the syringe body at the attachment surface; and introducing a
delivery mechanism into the proximal end of the incising shaft and
comprising a plunger longitudinally formed to slidably fit within
the bores of the syringe body and the incising shaft.
4. A method in accordance with claim 3, further comprising: forming
the incising shaft into a curve arced towards the delivery
mechanism.
5. A subcutaneous implantation instrument package, comprising: a
non-liquid implantable object; and a subcutaneous implantation
instrument packaged with the non-liquid implantable object,
comprising: a syringe body comprising a non-cylindrical shaft that
axially defines a non-circular bore continuously throughout the
length of the shaft, wherein the bore comprises a cross section of
at least five millimeters in at least one orientation; a
non-cylindrical incising shaft comprising: an incising shaft body
that axially defines a non-circular bore sized to match the bore of
the syringe body: a beveled cutting blade comprising a beveled
surface on a distal face of the incising shaft body and a straight
and sharpened cutting edge with rounded ends on each side of the
cutting edge that curve inwardly, wherein the cutting edge is
defined only along a bottom distal edge of the beveled tip; and an
attachment surface formed on a proximal end of the incising shaft
body, wherein the incising shaft is fixedly attached to a distal
end of the syringe body at the attachment surface; and a delivery
mechanism comprising a plunger longitudinally formed to slidably
fit within the bores of the syringe body and the incising
shaft.
6. A subcutaneous implantation instrument package in accordance
with claim 5, wherein the incising shaft is formed into a curve
arced towards the delivery mechanism.
7. A subcutaneous implantation instrument package in accordance
with claim 5, wherein the implantable object is selected from the
group comprising medical monitoring devices, diagnostic devices,
non-medical monitoring devices, data collection monitors, medical
therapeutic devices, solid objects, and semi-solid objects.
8. A method for constructing a subcutaneous implantation instrument
package, comprising: selecting a non-liquid implantable object; and
packaging a subcutaneous implantation instrument, comprising:
constructing a syringe body comprising a non-cylindrical shaft that
axially defines a non-circular bore continuously throughout the
length of the shaft, wherein the bore comprises a cross section of
at least five millimeters in at least one orientation; constructing
a non-cylindrical incising shaft comprising: forming an incising
shaft body that axially defines a non-circular bore sized to match
the bore of the syringe body; creating a beveled cutting blade
comprising a beveled surface on a distal face of the incising shaft
body and a straight and sharpened cutting edge with rounded ends on
each side of the cutting edge that curve inwardly, wherein the
cutting edge is defined only along a bottom distal edge of the
beveled tip; and forming an attachment surface formed on a proximal
end of the incising shaft body, wherein the incising shaft is
fixedly attached to a distal end of the syringe body at the
attachment surface; and introducing a delivery mechanism into the
proximal end of the incising shaft and comprising a plunger
longitudinally formed to slidably fit within the bores of the
syringe body and the incising shaft.
9. A method in accordance with claim 8, further comprising: forming
the incising shaft into a curve arced towards the delivery
mechanism.
10. A method in accordance with claim 8, wherein the implantable
object is selected from the group comprising medical monitoring
devices, diagnostic devices, non-medical monitoring devices, data
collection monitors, medical therapeutic devices, solid objects,
and semi-solid objects.
Description
FIELD OF THE INVENTION
The present invention relates in general to subcutaneous
implantation instruments and methods and, in particular, to an
instrument for implanting sensors and solid materials in a
subcutaneous location and method thereof.
BACKGROUND OF THE INVENTION
A major part of health care assessment involves the review and
analysis of physiological measurements collected and recorded by
electronic data sensors. In addition to vital signs, physiological
measures can include detailed measurements of organ functions, body
fluid chemistry and rates, activity levels, and similar measures,
both measured directly and derived.
The type and quality of physiological measures depends greatly on
the type and location of the sensor employed. External sensors,
such as thermometers, blood pressure cuffs, heart rate monitors,
and the like, constitute the most common, and least invasive, form
of sensors. However, these sensors are extremely limited in the
kinds of information which they are able to collect and encumber
the patient with wearing and maintaining an external sensor. On the
other extreme, implantable in situ sensors provide the most
accurate and continuous data stream through immediate proximity to
organs and tissue of interest. However, implantable sensors are
invasive and generally require surgery for implantation.
Recent advances in microchip technology have created a new
generation of highly integrated, implantable sensors. For instance,
PCT Application Nos. PCT/GB99/02389, to Habib et al., filed Jul.
22, 1998, pending, and PCT/GB99/02393, to Habib et al., filed Jul.
22, 1998, pending, respectively describe an implantable sensor chip
and treatment regiment, the disclosures of which are incorporated
herein by reference. The sensor chip is adapted to receive and
rectify incoming electromagnetic signals and to transmit data
relating to treatment parameters by wireless telemetry to a
receiver external to a body. Similarly, the emerging Bluetooth
wireless communication standard, described at
http://www.bluetooth.com/developer/specification/specification.asp,
proposes a low cost, small form factor solution to short range data
communications, potentially suitable for use in implantable sensor
technology.
Even though implantable sensor technology is trending towards
smaller and more specialized microchip sensors, in humans, these
sensors must still be implanted via surgical procedure. Minimally
invasive implantation using large bore needles is impracticable
because sensors, particularly when embodied using microchip
technology, favor a prismatic shape with substantially rectangular
cross sections. A large bore needle can cause a core of flesh or
skin (or hide, when used in domesticated animals) to form in the
pointed tip as the needle is inserted. Cylindrical needles also
severely limit solid sensor sizes, shapes and dimensions to only
those that can be inserted through a circular bore.
Although current surgical approaches attempt to minimize the size
of incision and decree of invasion, implantation is, at best,
costly, time-consuming, traumatic, requires multiple instruments
and maneuvers, and potentially risky to the patient. Subcutaneous
implantable sensors offer the best compromise between in situ
sensors and external sensors and are potentially insertable with a
simple injection. These sensors are typically implanted below the
dermis in the layer of subcutaneous fat. The subcutaneous
implantation of solid materials has been described in the prior art
as follows.
An insertion and tunneling tool for a subcutaneous wire patch
electrode is described in U.S. Pat. No. 5,300,106, to Dahl et al.,
issued Apr. 5, 1994. The tunneling tool includes a stylet and a
peel-away sheath. The tunneling tool is inserted into an incision
and the stylet is withdrawn once the tunneling tool reaches a
desired position. An electrode segment is inserted into the
subcutaneous tunnel and the peel-away sheath is removed. Although
providing a tool for subcutaneous implantation, the Dahl device
requires an incision into the subcutaneous fat layer and forms an
implantation site larger than the minimum sized required by the
electrode segment. Further more, the cylindrical bore precludes the
injection of non-conforming solid sensors or materials.
An implant system for animal identification that includes a device
for implanting an identification pellet in a fat layer beneath the
hide or skin of an animal is described in U.S. Pat. No. 4,909,250,
to Smith, issued Mar. 20, 1990. The device includes a curved
needle-like tube that terminates at a tapered, sharpened point. An
elongated, flexible plunger is slidably received within the
needle-like tube. The pointed tip is inserted through the hide or
skin and the plunger is actuated to drive the identification pellet
from the tip into the fat layer. However, the Smith device uses an
oversized open bore which can cause coring of the hide or
flesh.
A trocar for inserting implants is described in PCT Application No.
PCT/US99/08353, to Clarke et al., filed Oct. 29, 1999, pending. An
implant retention trocar includes a cannula for puncturing the skin
of an animal and an obturator for delivering the implant. A spring
element received within the cannula prevents an implant from
falling out during the implant process. The cannula has a distal
tip design which causes a minimum of trauma and tearing of tissue
during implant insertion. However, the distal tip design is
specifically directed to cannulas having a substantially circular
bore and thereby limits the size and shape of implant which can be
inserted through the Clarke trocar.
An instrument for injecting implants through animal hide is
described in U.S. Pat. No. 5,304,119, to Balaban et al., issued
Apr. 19, 1994. The instrument includes an injector having a tubular
body divided into two adjacent segments with a hollow interior
bore. A pair of laterally adjacent tines extend longitudinally from
the first segment to the distal end of the tubular body. A plunger
rod has an exterior diameter just slightly larger than the interior
diameter of the tubular body. With the second segment inserted
beneath the animal hide, the push rod is advanced longitudinally
through the tubular body, thereby pushing the implant through the
bore. As the implant and rod pass through the second segment, the
tines are forced radially away from each other, thereby dilating or
expanding the incision, and facilitating implant. The instrument is
removed from the incision following implantation. Though avoiding
the coring of animal hide or flesh, the instrument forms an
implantation site larger than the minimum sized required by the
implant and causes potentially damaging compaction of the implant
against the laterally adjacent times during implant delivery.
Therefore, there is need for a non-surgical instrument and method
for subcutaneous implantation of sensors and solid materials that
preferably does not require an incision preparatory to instrument
insertion.
There is a further need for a subcutaneous implantation instrument
and method capable of implanting sensors and other solid materials
that are not readily disposed to implantation through a
substantially circular bore.
Moreover, there is a further need for a subcutaneous implantation
instrument and method which is minimally invasive, preferably
creating the smallest needed implantation site, and capable of
implantation without exposing the implant to longitudinal
stresses.
SUMMARY OF THE INVENTION
The present invention provides an implantation instrument and
method of use for implanting sensors and other solid materials in a
subcutaneous or other site. As used herein, "subcutaneous" refers
generally to those implantation sites located within a body below
the skin. The implantation instrument consists of an incising shaft
attached to a syringe body. The syringe body and incising shaft
both define a substantially non-circular hollow bore for
accommodating the sensor or solid material. The subcutaneous site
is formed by a cutting edge on the distal end of the incising
shaft. The subcutaneous site can be cleared using a clearing trocar
slidably received within the hollow bore. The sensor or solid
material is advanced through the hollow bore and delivered into the
subcutaneous site. The depth of the subcutaneous site can be
limited using a penetration limiting mechanism.
An embodiment of the present invention is an implantation
instrument for implanting a substantially solid material in a
subcutaneous body location. An incising shaft defines a
substantially non-circular hollow bore extending continuously along
a longitudinal axis. The incising shaft has a beveled tip forming a
cutting edge on a distal end thereof and is sized to receive a
substantially solid material for implant. The solid material, which
can include a sensor, is preferably protected against damage by
encasement within, for example, a mannitol pellet or similar
carrier. The solid material can also be encased in titanium,
silicone, epoxy, or other similar, functionally inert protective
material. A delivery mechanism receives the incising shaft and
includes a pushing device facilitating deployment of the
substantially solid material through the incising shaft bore and
into an implantation site.
A further embodiment of the present invention is a subcutaneous
implantation instrument for implanting a substantially solid
material. An incising body includes a syringe body and an incising
shaft. The syringe body and the incising shaft each define a
substantially non-circular hollow bore extending continuously along
a shared longitudinal axis. The incising shaft includes a beveled
tip with a cutting edge on a distal end. Several prismatic or
non-cylindrical bore shapes are possible. The incising shaft bore
and the syringe body bore both are sized to receive the solid
material. A delivery assembly includes a plunger slidably fitted
within the syringe body bore. The plunger is conformably shaped to
the syringe body bore with an end piece facilitating deployment of
the substantially solid material into an implantation site.
A still further embodiment of the present invention is an
implantation instrument for implanting a substantially solid
material in a subcutaneous location. An incising shaft includes a
beveled tip with a cutting edge along a distal end thereof. A
syringe body is affixed to a proximal end of the incising shaft.
The syringe body and the incising shaft each define a substantially
non-circular hollow bore extending continuously along a shared
longitudinal axis. The incising shaft bore does not exceed the
syringe body bore in girth. Both the incising shaft bore and the
syringe body bore are sized to receive the solid material. A
plunger is conformably shaped to the syringe body bore and has an
end piece facilitating deployment of the plunger assembly, the
plunger slidably fits within the syringe body bore and advances the
solid material through the syringe body bore and the incising shaft
bore into the subcutaneous location.
A still further embodiment of the present invention is a method for
implanting a substantially solid material in a subcutaneous
location. A beveled tip of an incising shaft with a cutting edge
along a distal end thereof is inserted into an implantation site. A
proximal end of the incising shaft is affixed to a distal end of a
syringe body. The syringe body and the incising shaft each define a
substantially non-circular hollow bore extending continuously along
a shared longitudinal axis. The incising shaft bore do not exceed
the syringe body bore in girth. Both the incising shaft bore and
the syringe body bore are sized to receive the solid material. The
solid material is advanced through the syringe body bore and the
incising shaft bore into the subcutaneous location through
deployment of a plunger conformably shaped to the syringe body
bore. The deployment is effected via actuation of an end piece on a
distal end of the plunger. The plunger slidably fits within the
syringe body bore.
Still other embodiments of the present invention will become
readily apparent to those skilled in the art from the following
detailed description, wherein is described embodiments of the
invention by way of illustrating the best mode contemplated for
carrying out the invention. As will be realized, the invention is
capable of other and different embodiments and its several details
are capable of modifications in various obvious respects, all
without departing from the spirit and the scope of the present
invention. Accordingly, the drawings and detailed description are
to be regarded as illustrative in nature and not as
restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an instrument for implanting
sensors or solid materials in a subcutaneous or other tissue
location in accordance with the present invention;
FIG. 2A is a longitudinal cross-sectional view of the implantation
instrument with a straight incising shaft;
FIG. 2B is a longitudinal cross-sectional view of the implantation
instrument with a curved incising shaft;
FIG. 3 is a diagrammatic view illustrating the implantation of a
sensor or solid material into a subcutaneous site;
FIG. 4A is a diagrammatic view illustrating the clearing of a
subcutaneous site using the implantation instrument fitted with a
clearing trocar in accordance with a further embodiment;
FIG. 4B is a diagrammatic view illustrating the subcutaneous
implantation of a sensor using the implantation instrument fitted
with a pushing stylet in accordance with a further embodiment;
FIGS. 5A-D are transverse cross-sectional views of the implantation
instrument illustrating, by way of example, various bore
configurations;
FIG. 6 is a segmented side view of a clearing trocar;
FIG. 7 is a segmented side view of a pushing stylet; and
FIGS. 8A-8B are section views illustrating penetration limiting
mechanisms for use with the implantation instrument; and
FIG. 9 is a perspective view of an instrument for implanting
sensors or solid materials in a subcutaneous or other tissue
location in accordance with a further embodiment of the present
invention.
DETAILED DESCRIPTION
FIG. 1 is a perspective view of an instrument 10 for implanting
sensors or solid materials in a subcutaneous or other tissue
location in accordance with the present invention. The implantation
instrument 10 consists of two principal groups of components, an
incising body consisting of an incising shaft 11 and a syringe body
15, and a delivery assembly consisting of a plunger assembly 20.
The delivery assembly is received into the syringe body bore by
sliding the plunger assembly 20 through proximal bore opening
19.
The incising shaft 11 is formed with a beveled and rounded tip 12
that tapers into a surgically sharp cutting edge 13 formed on a
distal edge. The beveled tip 12 includes a distal bore opening 14
through which the sensor or solid material is delivered into the
implantation site.
In the described embodiment, the sensor or solid material (implant)
has approximate dimensions of 5 mm by 10 mm by 20 mm. The critical
dimension is the cross-sectional profile, that is, the height and
width, of the implant which must conform to passage through the
syringe body and incising shaft bores. Other non-linear, prismatic
shapes are equally usable provided the implant can fit within the
confines of the syringe body and incising shaft bores. The implant
could also be folded or compacted to minimize the cross-sectional
profile with the implant unfolding or expanding upon implantation.
As well, the implant is preferably protected against damage by
encasement within, for example, a mannitol pellet in the case of a
solid drug delivery system or epoxy in the case of an implantable
sensor.
An implantable sensor microchip suitable for use in the present
invention is described in PCT Application No. PCT/GB99/02389, to
Habib et al., filed Jul. 22, 1998, pending, the disclosure of which
is incorporated herein by reference. Such a sensor could be used
for monitoring and collecting physiological or chemical measures.
Similar devices for therapeutic uses, including treating cancer,
and for health care giving, including administering solid
medication in the form of boluses, are possible. As well, the
present invention has equal applicability to implantation of
sensors, including location and identification sensors, and solid
materials in domesticated animals. The sensor could also constitute
or include a data transmitter with which to exchange information
and telemetered signals.
The incising shaft 11 is fixably attached to the syringe body 15
through frictional, adhesive, or preformed constructive means, as
is known in the art. Both the incising shaft 11 and syringe body 15
define a substantially non-circular hollow bore extending
continuously along a shared longitudinal axis, as further described
below with reference to FIGS. 5A-D.
The plunger assembly includes a plunger 16, an interconnecting
plunger shaft 17 and a plunger end piece 18. The plunger 16 is
conformably shaped to fit within the syringe body bore. The plunger
end piece 18 facilitates deployment of the plunger assembly through
the syringe body bore and is preferably shaped to fit a thumb or
palm impression.
In the described embodiment, the implantation instrument 10 is
designed for inexpensive and disposable use utilizing low-cost,
sanitizable materials. The incising shaft 11 can be fashioned from
surgical grade stainless steel and has the approximate dimensions
of approximately 10 mm by 5 mm in cross section. The incising shaft
11 is approximately 50 mm long and the length can be varied to
accommodate different implantation depths. The plunger 16 is formed
from plastic and rubber and preferably forms a watertight seal
within the syringe body bore and has the approximate dimensions of
approximately 8 mm by 3 mm in cross section. The plunger shaft 17
and plunger end piece 18 are formed from plastic or similar
material. Other materials, as would be recognized by one skilled in
the art, could be substituted.
In a further embodiment, the syringe body 15 and plunger assembly
can be replaced by an automated injection system, such as used with
immunization injection guns or similar devices. These devices
typically employ compressed air or other inert gases to administer
medication in lieu of manual plungers. Other automated variations
include spring-loaded and similar mechanical injection systems. The
incising shaft 11 is fixably attached to the automated injection
system which functions as a delivery mechanism in place of the
syringe body 15 and plunger assembly. Thus, the implant would be
pushed through the incising shaft bore using the compressed air or
gas, or mechanical equivalent.
FIG. 2A is a longitudinal cross-sectional view of the implantation
instrument 10 with a straight incising shaft 11. The hollow bore
defined by both the incising shaft 11 and the syringe body 15 runs
along a common shared axis. The incising shaft bore 22 is sized to
allow the implant to advance smoothly into the implantation site
under the forward lateral urging of the plunger assembly 20. The
syringe body bore 23 must be at least as large as the incising
shaft bore 22, but can be slightly larger to accommodate
lubricants, anesthetizing agents, or similar coatings, such as
mannitol, applied over the sensor or solid material.
The syringe body 15 preferably includes a circular collar 21, pair
of winglets, ears, or eyelets, or similar structure, optionally
formed on a proximal end of the syringe body 15 to assist a user in
depressing the plunger assembly 20.
FIG. 2B is a longitudinal cross-sectional view of the implantation
instrument with a curved incising shaft 24. The curved incising
shaft 24, as well as the syringe body 15 and related components,
are shaped into a substantially continuous curve along the ventral
side. The curvature helps regulate the penetration depth of the
incising shaft and, in the described embodiment, has an arc of
approximately 20 degrees.
FIG. 3 is a diagrammatic view illustrating the implantation of a
sensor 28 or solid material into a subcutaneous site. Prior to
delivery, the sensor 28 is fed through the proximal bore opening 19
of the syringe body 15 and then further advanced through the
syringe body bore 23. During operation, the incising shaft 11 is
inserted through the dermis 25 and guided into the layer of
subcutaneous fat 26, above the layer of muscle 27. The sensor 28 is
then advanced through the incising shaft bore 22 by the plunger 16
into the subcutaneous site. Note that although the foregoing view
illustrates an implant into the subcutaneous fat layer, one skilled
in the art would appreciate that subcutaneous implantation
locations are not strictly limited to the subcutaneous fat layer
and are generally termed as those implantation locations situated
within a body under the skin.
FIG. 4A is a diagrammatic view illustrating the clearing of a
subcutaneous site using the implantation instrument 10 fitted with
a clearing trocar 29 in accordance with a further embodiment. The
clearing trocar 29, as further described below with reference to
FIG. 6, is mounted to its own handle or plunger assembly and has a
sharp cutting tip 30 for optionally clearing a subcutaneous site
prior to delivery of the implant.
Prior to implantation, the clearing trocar 29 is slidably received
into the syringe body 15 and is advanced until the cutting tip 30
is even with the proximal bore opening 19 of the incising shaft 11.
During operation, the incising shaft 11 and clearing trocar 29 are
inserted through the dermis 25 and guided into the layer of
subcutaneous fat 26, above the layer of muscle 27.
The cutting edge 13 of the beveled tip 12 makes an entry incision
through the dermis 25 and is laterally pushed into the subcutaneous
fat 26 until the cutting edge 13 is adjacent to the subcutaneous
site. The clearing trocar 29 is then urged through the subcutaneous
fat 26 by advancement of its handle or plunger assembly to prepare
the implantation site for delivery of the sensor 28 or solid
material. The clearing trocar 29 is then withdrawn from the
subcutaneous site and out of the implantation instrument 10.
FIG. 4B is a diagrammatic view illustrating the subcutaneous
implantation of a sensor 28 using the implantation instrument 10
fitted with a pushing stylet 31 in accordance with a further
embodiment. The pushing stylet 31, as further described below with
reference to FIG. 7, has a blunt tip 32 for advancing the sensor 28
(or solid material) through the syringe body bore 23 and incising
shaft bore 22 and into the subcutaneous site. The cross section of
the pushing stylet 31 closely conforms to the incising shaft bore
22 while the plunger 16 closely conforms to the syringe body bore
23. The pushing stylet 31 thus extends the reach of the plunger
assembly 20 and allows the syringe body bore 23 to have a different
cross-section than the incising shaft bore 22.
The pushing stylet 31 is used while the incising shaft 11 is in
situ in the subcutaneous layer 26. Prior to delivery, the sensor 28
is fed through the proximal bore opening 19 of the syringe body 15
and further advanced within the syringe body bore 23 by contact
with the plunger 16. The pushing stylet 31 is slidably received
into the syringe body 15 and is advanced until the blunt tip 32
contacts the sensor 28. During operation, the sensor 28 is urged
through the incising shaft bore 22 by the pushing stylet 31 and
into the subcutaneous site by advancement of the plunger assembly.
Upon delivery of the sensor 28 into the subcutaneous site, the
incising shaft 11 and pushing stylet 31 are withdrawn.
Although operation of the implantation instrument 10 is described
with reference to the implantation of sensors or solid materials
into a subcutaneous site situated within the layer of subcutaneous
fat 26, implantations could also be effected in other subcutaneous,
intramuscular, intraperitoneal, intrathoracic, intracranial,
intrajoint, as well as other organ or non-subcutaneous sites, as
would be recognized by one skilled in the art. In addition, the
foregoing procedure could be modified to forego the use of the
clearing trocar 29 for small sensors 28 or solid materials. The
clearing effect of the clearing trocar 29 can be approximated by
use of the incising shaft 11 alone whereby the incising shaft 11 is
inserted into the subcutaneous site and then withdrawn by reverse
deployment, thereby forming a slightly overwide implantation
site.
The operations of subcutaneous implantation can be carried out over
a plurality of sites and with the same or different sensors 28 and
solid materials. Similarly, several sensors 28 and solid materials
could be implanted at the same subcutaneous site during a single
implantation operation.
FIGS. 5A-D are transverse cross-sectional views of the implantation
instrument 10 illustrating, by way of example, various bore
configurations. FIG. 5A illustrates an incising shaft 35 with a
substantially rectangular bore 36. FIG. 5B illustrates an incising
shaft 37 with a substantially square bore 38. FIG. 5C illustrates
an incising shaft 39 with a substantially oval bore 40. And FIG. 5D
illustrates an incising shaft 41 with a substantially hexagonal
bore 42. Note the circumferential shape of the incising shaft need
not follow the internal shape of the incising shaft bore. Other
bore configurations, including variations on oval, rectangular,
square, pentagonal, hexagonal, heptagonal, octagonal, and similar
equilateral or non-equilateral shapes, are feasible.
In the described embodiment, the rectangular bore 36 has the
dimensions of approximately 10 mm by 5 mm. The syringe body bore 23
has a length of approximately 5 cm.
FIG. 6 is a segmented side view of a clearing trocar 45. The
clearing trocar 45 consists of a beveled tip 47 on the distal end
of the clearing trocar 45 and a clearing trocar shaft 46 affixed,
either fixably or removably, to the distal end of a plunger 16.
During a clearing operation, the clearing trocar 45 is fully
extended from the distal bore opening 14 of the incising shaft 11.
The clearing trocar shaft 46 is only long enough to clear out the
subcutaneous site. The plunger 16 acts as a stop that limits the
extent of penetration of the clearing trocar 45, thereby preventing
the clearing trocar 29 from incising too deeply into the
subcutaneous fat 29. In addition, the clearing trocar 29 is sized
to approximate the girth of the incising shaft bore 22 and will
clear a subcutaneous site only as wide as minimally necessary to
facilitate implantation of the sensor or solid material. In the
described embodiment, the clearing trocar 45 has a length of
approximately 2 cm beyond the tip of the syringe body 15.
FIG. 7 is a segmented side view of a pushing stylet 50. The pushing
stylet 50 consists of a blunt tip 52 on the distal end of the
pushing stylet 50 and a pushing stylet shaft 51 affixed, either
fixably or removably, to the distal end of a plunger 16.
During a delivery operation, the pushing stylet 50 is extended from
the distal bore opening 14 of the incising shaft 11. The pushing
stylet shaft 51 is only long enough to clear the distal bore
opening 14. The plunger 16 acts as a stop that limits the lateral
travel of the pushing stylet 50. In the described embodiment, the
pushing stylet 50 has an additional length of approximately 2 cm
beyond the tip of the syringe body 15.
FIGS. 8A-8B are section views illustrating penetration limiting
mechanisms for use with the implantation instrument 10. The
penetration limiting mechanisms limit the depth of penetration of
the incising shaft 11 and help prevent excessive penetration. FIG.
8A shows a fixed penetration limiting mechanism consisting of a
stopping flange 55 attached to the incising shaft 11. The position
of the stopping flange 55 along the incising shaft 11 can be
adjusted by loosening a hold-down screw 58 and sliding the stopping
flange 55 into the desired location. The lower edge of the stopping
flange 55 has a bend 57 with an angle .tau., preferably between
approximately 30.degree. and 60.degree., thereby forming an elbow
56 which stops lateral travel upon contact with the skin.
FIG. 8B shows an adjustable penetration limiting mechanism
consisting of a stopping flange 60 attached a frictional collar 64.
The stopping flange 60 and frictional collar 64 are slidably
attached to the incising shaft 11. An adjustable collar 64,
preferably in threaded communication 65 with the frictional collar
64, manually stops deployment of the penetration limiting mechanism
by tightening the frictional collar 64 against the incising shaft
11. The lower edge of the stopping flange 60 has a bend 62 with an
angle .upsilon., preferably between approximately 30.degree. and
60.degree., thereby forming an elbow 61 which stops lateral travel
upon contact with the skin.
FIG. 9 is a perspective view of an instrument for implanting
sensors or solid materials in a subcutaneous or other tissue
location in accordance with a further embodiment of the present
invention. The instrument is equipped with the stopping flange 55
shown in FIG. 8A. Other forms of penetration limiting mechanisms,
both fixed and adjustable, could be used, as would be readily
apparent to one skilled in the art.
While the invention has been particularly shown and described as
referenced to the embodiments thereof, those skilled in the art
will understand that the foregoing and other changes in form and
detail may be made therein without departing from the spirit and
scope of the invention.
* * * * *
References